A case of massive left atrial lipoma occupying pericardial space.

We report a rare case of massive left atrial lipoma occupying pericardial space. A 52-year-old male was admitted because of cardiomegaly of unknown etiology. Computed tomography showed a large epicardial mass located along the anterior surface of the heart, from the diaphragm level through the aortic arch level. The mass showed an attenuation value identical with that of subcutaneous adipose tissue and contained some areas with high density. The mass was not enhanced by contrast media. Histologic examination of the specimen obtained by percutaneous biopsy demonstrated mature adipose tissue. An encapsulated adipose mass weighing 620 g, which originated from the left atrium without any invasion to the pericardium, was completely excised. Microscopic examination revealed mature adipose tissue with partial necrosis, confirming the diagnosis of lipoma.